Broccoli Ingredient May Fight Bladder Cancer
Researchers Identify Chemical Behind Broccoli's Cancer-Fighting Effects
Aug. 3, 2005 -- The crunch may be the key behind broccoli's cancer-fighting
effects, according to a new study.
A previous study showed that men who ate two or more servings of broccoli
per week had a 44% lower risk of bladder cancer than those who ate less than
one serving a week.
Now researchers say they may have found at least one ingredient in the
cruciferous vegetable responsible for this beneficial effect, and it's only
released after chopping, chewing, or digesting broccoli.
"We're starting to look at which compounds in broccoli could inhibit or
decrease the growth of cancerous cells," says researcher Steven Schwartz,
professor of food science and technology at Ohio State University, in a news
release. "Knowing that could help us create functional foods that benefit
health beyond providing just basic nutrition."
Broccoli's Cancer-Fighting Chemicals
First, researchers isolated a group of chemicals called glucosinolates,
which are found naturally in crunchy, cruciferous vegetables. These chemicals
are converted into compounds known as isothiocyanates during chopping, chewing,
Then they tested the ability of both chemicals to stop the growth of bladder
cancer cells in the lab.
The results showed that the group of chemicals derived from chopping,
chewing, and digesting broccoli (the isothiocyanates) halted the growth of even
the most powerful form of bladder cancer cells. But glucosinolates, from which
isothiocyanates are derived, had no effect.
"There's no reason to believe that this is the only compound in broccoli
that has an anti-cancer effect," says researcher Steven Clinton, associate
professor of hematology and oncology at Ohio State University, in the release.
"There are at least a dozen interesting compounds in the
"We're now studying more of those compounds to determine if they work
together or independently, and what kind of effects they have on cancer
cells," says Clinton.
Researchers presented the results of the study at a recent conference of the
Institute of Food Technologists.
They say young broccoli sprouts naturally contain higher levels of these
chemicals than full-grown broccoli spears. But eating the spears still appears
to provide health benefits.
It's too early to say just how much broccoli or broccoli sprouts a person
needs to eat to prevent or slow down the progression of bladder cancer. Other
cruciferous vegetables, such as cabbage, brussels sprouts, and cauliflower, may
also contain similar cancer-fighting chemicals.